Granite, I understand how very scary new things can be...how frightening not knowing what to expect can be. Perhaps you could extend just a tiny bit of trust to your T, that she's doing this to help you, not get rid of you. That letting her teach you mindfulness will allow her to better help you, because it will give you both a common frame of communication.

Mindfulness is not really something you can fail at, unless you don't even try. It takes practice, yes, but learning to do anything new takes practice. It's okay to be scared, you can even be mindful of that scared part while doing the exercises!

As I posted in Skysblue's thread, I have found that mindfulness exercises are about the only way I can get grounded when I'm seriously disconnected. It doesn't have to be anything complex or deep or earth-shattering. It's just focusing on a single moment and noticing everything about that moment without judging it. I usually just focus on my breathing and then when I'm totally focused on that, I let myself expand my senses outward...what do I hear, what do I see (unless I've closed my eyes), what do I feel physically (a/c blowing on me, sun on my skin, etc)...if I feel able, then I go deeper to what my body and emotions are doing...but only if I feel able...sometimes it's enough to just notice the world around me.